Substrate processing apparatus, method of manufacturing semiconductor device, and recording medium

A substrate processing apparatus comprising:

• a process chamber configured to process a substrate mounted on a substrate support as a heated boat for supporting a plurality of substrates in a vertical direction;
• a transfer chamber in communication with a lower portion of the process chamber in the vertical direction;
• a heating chamber in communication with a lower portion of the transfer chamber in the vertical direction;
• wherein the transfer chamber is configured to transfer the processed substrate of the plurality of substrates out of the substrate support via a substrate loading port while a portion of the substrate support in which an unprocessed substrate of the plurality of substrates is held is positioned in the heating chamber, and
• wherein the heating chamber is configured such that the unprocessed substrate of the plurality of substrates supported in the portion of the substrate support is heated therein at a first temperature by the heated boat while the processed substrate is transferred out of the substrate support after being heated to a second temperature greater than the first temperature;
• wherein the transfer chamber is further configured to transfer another unprocessed substrate of the plurality of substrates onto the substrate support via the substrate loading port after the processed substrate is transferred out of the substrate support.